The present application relates generally to the field of fuel cell systems and more specifically to a fuel cell system where pressure is balanced between an anode and cathode of a fuel cell in the system.
In conventional high-temperature fuel cells, the anode and cathode of a fuel cell operate at different pressures, which reduces fuel cell efficiency and reduces the operational life of the fuel cell. For example, when pressure in the anode is greater than pressure in the cathode, anode feed gas may leak (crossover) from the anode, across the membrane, and to the cathode. In this configuration, at least a portion of the anode feed gas is not utilized for electricity production within the fuel cell, thereby reducing operational efficiency of the fuel cell. The anode feed gas, which crosses over to the cathode may also oxidize (i.e., burn) within the cathode cavity, resulting in the loss of oxygen and an undesirable localized temperature increase, which shortens the operating life of the fuel cell. In contrast, if pressure in the cathode is greater than pressure in the anode, cathode feed gas may crossover to the anode, resulting in possible oxidation of the catalyst within the anode and/or oxidation of the fuel within the anode chamber, which also produces a localized temperature increase. In each of these cases, the crossover of feed gas to or from the cathode may damage the anode and reduce the operational life of the fuel cell.
It would be advantageous to provide a fuel cell system that balances the pressure between the anode and the cathode of a fuel cell. As will be appreciated by those reviewing the present disclosure, these and other advantages may be obtained using the exemplary embodiments disclosed herein.